In this article, we present Dendro, a suite of parallel algorithms for the discretization and solution of partial differential equations (PDEs) involving second-order elliptic operators. Dendro uses trilinear finite element discretizations constructed using octrees. Dendro, comprises four main modules: a bottom-up octree generation and 2:1 balancing module, a meshing module, a geometric multiplicative multigrid module, and a module for adaptive mesh refinement (AMR). Here, we focus on the multigrid and AMR modules. The key features of Dendro are coarsening/refinement, inter-octree transfers of scalar and vector fields, and parallel partition of multilevel octree forests. We describe a bottom-up algorithm for constructing the coarser multigrid levels. The input is an arbitrary 2:1 balanced octree-based mesh, representing the fine level mesh. The output is a set of octrees and meshes that are used in the multigrid sweeps. Also, we describe matrix-free implementations for the discretized PDE operators and the intergrid transfer operations. We present results on up to 4096 CPUs on the Cray XT3 ("BigBen") , the Intel 64 system ("Abe"), and the Sun Constellation Linux cluster ("Ranger").

Modifications to a standard capacitive MEMS switch process have been made to allow the incorporation of ultra-nano-crystalline diamond as the switch dielectric. The impact on electromechanical performance is minimal. However, these devices exhibit uniquely different charging characteristics, with charging and discharging time constants 5-6 orders of magnitude quicker than conventional materials. This operation opens the possibility of devices which have no adverse effects of dielectric charging and can be operated near-continuously in the actuated state without significant degradation in reliability.

Diabetes mellitus is a major health problem and it is a metabolic disorder characterized by hyperglycemia. Decreased utilization of glucose by the body cells and continuous raise in the plasma glucose levels are the major characteristic symptoms of diabetes. Uncontrolled hyperglycemia is associated with pathological conditions, mostly micro and macrovascular. Treatment for diabetes is aimed at the management of hyperglycemia using oral hypoglycemic agents which inhibit carbohydrate degrading enzymes, namely amylase and glucosidase. The purpose of this study was to investigate the naturally available inhibitors of amylase and glucosidase present in the peels of citrus fruits such as lemon and orange. The hydroalcoholic extract of the fruit peels were studied for their amylase and glucosidase inhibitory potential and the extract of lemon peel was found to exhibit better inhibition than the orange peel. The extracts were further evaluated for their additive effect. The combined effect of the extracts (50% inhibition achieved at 40 and 80mcg) proved to exhibit better inhibitory potential than the individual effect (50% inhibition achieved at 80 and 160mcg). Thus, from this study, it was very clear that our choice drug sources is containing potential antidiabetic principles that need to be studied further to understand the mechanism of action in detail.

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Adding alloying elements like copper (Cu) and zirconium (Zr) to binary NiTi shape memory alloys (NiTiCuZr SMA) raises the martensitic transition temperatures and functional fatigue properties while maintaining high corrosion and wear resistance. Therefore, it is essential to make high-precision SMA components with less damage to be machined into various complex shapes, sizes, and surface topographies to meet the needs of several engineering applications. In this research work, advanced machining processes like wire electrical discharge machining (WEDM) and fiber laser machining were employed to machine NiTiCuZr SMA and study their processing parameters' effects on the surface roughness, topography changes, and surface hardness. 3D surface topography and surface roughness on the machined surfaces were evaluated through contact and non-contact measurement techniques. The differential scanning calorimetry (DSC) test was conducted on the NiTiCuZr SMA before and after machining to confirm changes in the shape memory properties. When both processes were used at high energy levels, the formation of the resolidified layer and surface defects were more pronounced, increasing surface roughness. DSC curves for heating and cooling profiles show similar transformation temperatures for WEDM and laser machined NiTiCuZr SMA. On comparing two different machining processes, the WEDM process resulted in the Ra (µm) being 28.2% lower, the surface topography was smooth, and the microhardness was 11.9% lower than the samples machined using laser machining. This shows that machining of NiTiCuZr SMA using WEDM gives a better surface finish, reaching a fair decision that WEDM is a better alternative to laser machining.